Split daemon mode configs from core configs

[silvanocerza]

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• The PR has no duplicates (please search among the Pull Requests
  before creating one)
• The PR follows
  our contributing guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)
• UPGRADING.md has been updated with a migration guide (for breaking changes)

• What kind of change does this PR introduce?

This PR reworks how daemon settings are handled.

• What is the current behavior?

Currently the settings used by the Arduino CLI when running in daemon or command line mode are shared and stored in the same file, usually ~/.arduino15/arduino-cli.yaml depending on the OS.

This causes some problems since it's not possible to use a single daemon process for multiple users with different settings because they are shared for all the internal instances. The daemon mode settings are strictly tied to the command line mode settings in other terms.

• What is the new behavior?

The daemon.* settings have been removed from the config read by the arduino-cli when running in command line mode.

The arduino-cli daemon now doesn't read the same config file as the other commands, the --config-file flag is still
present but reads a file with the following keys:

• ip: IP used to listen for gRPC connections
• port: Port used listen for gRPC connections
• daemonize: True to run daemon process in background
• debug: True to enable debug logging of gRPC calls
• debug-filter: List of gRPC calls to log when in debug mode
• verbose: True to print logs in stdout
• format: Stdout output format
• no-color: True to disable color output to stdout and stderr
• log-level: Messages with this level and above will be logged
• log-file: Path to the file where logs will be written
• log-format: Output format for the logs

The format of the file can be yaml, json, hcl, toml or ini. An example daemon-config.yaml file could look
like this:

ip: "0.0.0.0"
port: "0"
verbose: true
format: "json"

All the settings in the config file can be override with the following flags:

• --ip
• --port
• --daemonize
• --debug
• --debug-filter
• --verbose, -v
• --format
• --no-color
• --log-level
• --log-file
• --log-format

None of those settings will be read from the default arduino-cli.yaml file stored in the .arduino15 or Arduino15
folder anymore when running the arduino-cli daemon command.

Those that start the daemon process will be tasked to manage the config file used by it.

• Does this PR introduce a breaking change, and is
  titled accordingly?

Yes.

• Other information:

This is the first PR of a series of breaking changes to enhance how the configs are handled internally by the arduino-cli.

This PR breaks the handling of configs when running the arduino-cli in daemon mode since we're changing the behaviour of the --config-file flag for that command.

This will be fixed in a subsequent PR that move the internal storaging of configs from a global variable to the CoreInstance struct.

This PR closes #1620.

---

See how to contribute

[silvanocerza]

This PR also adds the possibility to customize the IP used in daemon mode so it supersedes #1616.

[cmaglie]

Overall looks good. Maybe it's worth opening a feature branch?

[silvanocerza]

@per1234 docs updated. Thanks for the great suggestions. 👍

[per1234]

Thanks Silvano!

My only remaining concern is whether the [breaking] prefix should be added to the PR/commit title as specified in the contributor guide:
https://arduino.github.io/arduino-cli/dev/CONTRIBUTING/#breaking

[silvanocerza]

@per1234 I added it after merging, in any case for the time being this lives on a feature branch.